How do users design? The case of sugar cane harvester machines.

BACKGROUND: Design in use and inventiveness are key concepts in ergonomics. It is well-known that users design but is not explored in the literature how they manage to do that.

OBJECTIVE: This paper aims to contribute to the discussion of how users actually design, by showing a research conducted in sugar cane harvesting in Brazil and in Australia.

METHODS: Through the methodology of the Ergonomic Work Analysis (EWA), the design modifications made by the harvesting teams were identified as well as their elaboration process.

RESULTS: Three categories of modifications in machines' design were identified: structural, functional and operational and they were more numerous in Brazilian situations. It is proposed that two theories underlying the theme are intertwined: the instrument-mediated activity approach and the design as bricolage.

CONCLUSIONS: It is argued that users design through the articulation of: a) the operators' activity, b) the mechanical technicians' inventory to practice bricolage as a way of designing and c) the work organisation and the existence of social spaces of interaction between these two subjects.